1. Field of the Invention
The present invention relates to the field of burners, in particular burners for use in gas turbines. It relates to a burner with fuel supply system, in which the fuel supply system transports fuel to the burner, and the fuel in the burner is injected into a combustion chamber where the fuel is burned.
2. Discussion of Background
Burners of gas turbines serve the purpose of injecting the fuel and the combustion air in a way which is controlled and can be regulated into a combustion chamber, and of burning the fuel there, For this purpose, the burners can be recessed in a most varied arrangement in the wall of the combustion chamber, and are charged with fuel by means of a fuel supply system. In order to ensure optimum control of the combustion process in the various operating states of the turbine, the injection of the fuel in the burner must be performed controllably and as optimally as possible. Precisely the regulations to be observed ever more strictly in recent time and relating to the emission from combustion processes are now rendering mandatory a highly specialized and complicated injection and mixing of combustion air and fuel in the burner.
For example, EP-B1-0 321 809 -has disclosed a so-called double-cone burner for liquid and gaseous fuels without a pre-mixing section, in which combustion air fed from outside enters tangentially, through at least two entrance slots, between hollow half cones arranged in a displaced fashion, and flows there in the direction of the combustion chamber, and in which, on the tapered side, averted from the combustion chamber, of the half cones, fuel is injected centrally, or from distribution channels, which run along the air entry slots, through rows of bores transversely into the air which is entering.
A problem with the injection of the fuel and its subsequent combustion are, inter alia, acoustic oscillations, which are also known under the term of "singing flame". These are mostly oscillations which come about from the interplay between the inflow of the combustion mixture and the actual combustion process in the combustion chamber. These largely coherently periodic pressure fluctuations can lead in the case, for example, of a burner of the above-named type under typical operating conditions to acoustic fluctuations with frequencies of approximately 80 to 100 Hz. Since these frequencies can coincide with typical fundamental natural modes of combustion chambers of gas turbines, these thermo-acoustic oscillations constitute a problem.